The Psychological Laboratory and the Psychological Experiment 13complex behaviors as reasoning and problem solving rather
than to denote differences among species in adapting to the
environment, the more common use of the term in the nine-
teenth century.
James McKeen Cattell, who had studied with Hall at
Johns Hopkins before earning his PhD with Wundt, pur-
sued his interest in individual variation, labeled “ganz
Amerikanisch”by Wundt (Boring, 1950), while in Francis
Galton’s London laboratory. Cattell returned to establish a
laboratory at Columbia University and adapted laboratory
tasks familiar to him from both Leipzig and London to iden-
tify and measure differences in reaction time, sensory sensi-
tivity, time estimation, and memory span in undergraduate
students (Sokal, 1987; Tuddenham, 1962). Like Galton, he
theorized that such tasks as reaction time, sensory acuity,
memory, and apprehension spans would reveal an individ-
ual’s intellectual abilities. His attempt to relate scores on
these tasks to academic performance demonstrated little rela-
tionship between the performance scores on the laboratory
tests to academic performance in courses at Columbia (Sokal,
1987) but nevertheless represents an early effort to measure
the intelligence of individuals.
Assessing individual differences among human beings did
not necessarily result in appropriate conclusions about the
consequences of evolution because of the importance of
social and cultural factors in determining differences among
individuals. For example, Galton’s study of sex differences in
psychological characteristics reflected social and cultural
views of the capabilities and proper roles for women and men
rather than differences that could be attributed to evolution-
ary forces. This bias was common at the time and addressed
by the research of one of James R. Angell’s graduate
students, Helen Bradford Thompson. Her dissertation, com-
pleted at the University of Chicago in 1900 and later pub-
lished as The Mental Traits of Sex (1903), was the first
systematic, experimental investigation of sex differences in
motor ability, sensations, intellect, and affect. Careful, de-
tailed analysis of the results led to her conclusion that “the
psychological differences of sex seem to be largely due, not
to difference of average capacity, nor to difference in type of
mental activity, but to differences in the social influences
brought to bear on the developing individual from early
infancy to adult years” (p. 182).
Hall, too, had employed evolutionary arguments to bolster
stereotyped ideas about the psychological nature and proper
roles of men and women. His rather unflattering assessment
of women’s abilities attracted little argument from American
male psychologists of the time (see Diehl, 1986; Shields,
1975) and played a role in denying opportunities for graduate
study and professional employment for women (Milar, 2000).
In 1910, Helen Thompson, writing under her married name,
Helen Thompson Woolley, reviewed the literature on sex dif-
ferences and asserted, “There is perhaps no field aspiring to
be scientific where flagrant personal bias, logic martyred in
the cause of supporting a prejudice, unfounded assertions,
and even sentimental rot and drivel, have run riot to such an
extent as here” (Woolley, 1910, p. 340). Similar conclusions
could have been drawn about comparisons among races
begun before the development of evolutionary theory. These
comparisons had also served to justify a hierarchy that placed
Caucasians in a superior position, and later studies under
the aegis of evolutionary theory continued to be carried out
and interpreted in terms of long-held cultural biases (see
R. Guthrie, 1998).
Influenced by Cattell and Hall’s child study movement,
Lightner Witmer (1867–1956), attempted to put performance
on laboratory tasks to practical use in the new discipline
that he labeled “Clinical Psychology” (McReynolds, 1996).
The apparatus and methods of the laboratory experiment
were successful in assessing differences among individuals
but proved to be of little value for Witmer’s purposes
(McReynolds, 1996). The failure of laboratory tasks for these
applied ends led, in the case of intelligence testing, to the
refinement and development of tests modeled on those of
Alfred Binet and, in Witmer’s case, to the search for more
suitable methods for assisting individuals. These efforts also
led to attempts to identify characteristics of individuals that,
like intelligence, were both measurable and offered promise
of relevance, such as personality assessment (Allport, 1937),
attitude and aptitude measures, and clinical diagnostic tests
(Gregory, 1992). For many psychologists, individual differ-
ences were a distraction to the understanding of the general
principles governing mind, while for others, the understand-
ing of the individual mind was the most interesting task for
psychology. The difference in emphasis and the somewhat
separate paths of development of the two pursuits within psy-
chology came to be seen as the two disciplines of scientific
psychology (Cronbach, 1957).The Study of Nonhumans: Animal PsychologyDarwin’s theory of evolution had raised questions about the
adaptive utility of consciousness; the relation of human to
animal ancestry had raised issues of whether there are instincts
in humans and whether animals exhibited human intellectual
capacities and consciousness in adapting to changed or chang-
ing environments. Learning capacities and consciousness
seemed in turn to depend upon the complexity of the nervous
system: “If there is a Comparative Anatomy there is also a
Comparative Psychology” (Chadbourne, 1872, p. 22). George